During manufacture of microelectromechanical systems (MEMS) or other semiconductor elements, an etching of deep openings, trenches or cavities from a back side of a substrate/carrier extending to a front side of the substrate may often be required.
For a good functionality of the final element, it may be essential that a relative positioning (adjustment) of a backside mask with respect to structures on the front side of the substrate is precise. Furthermore, the positioning of structures defined by the mask on the back side of the substrate may need to be transferred precisely to the front side of the substrate, and a shape of the structures defined on the back side may need to be conserved during the transfer from the back side to the front side of the substrate, such that openings/trenches/cavities having been formed in the substrate from the backside and opening up on the front side of the substrate are precisely positioned with respect to the front side structures and have an intended shape.
Such aspects may for example be relevant in the manufacturing of silicon microphones or loudspeakers.